US20100222846A1 - Remotely- requested integrity diagnostics - Google Patents

Abstract

In general, the invention is directed toward techniques for remotely monitoring the integrity of a medical device and its components. A remote networking device communicates with a medical device, e.g., an implantable medical device, via a network. The remote networking device sends a request for an integrity measurement to the medical device via the network, a remote network that requests a medical device to perform an integrity measurement. In response to the request, the medical device performs the requested integrity measurement. The medical device may transmit a result of the integrity measurement, e.g., a measured value, back to the remote networking device via the network.

Description

TECHNICAL FIELD
• The invention relates to medical devices, and more particularly to integrity diagnostics for medical devices.
BACKGROUND
• Medical devices may be used to treat a variety of medical conditions. Depending upon the medical condition, medical devices can be surgically implanted within, or connected externally to the patient receiving treatment. For some medical conditions, medical devices provide the best or only therapy to restore an individual to a more healthful condition and a fuller life. Examples of medical devices that deliver a therapy include electrical stimulators and therapeutic agent delivery devices.
• If one or more components of a medical device are damaged or otherwise fail to operate as intended, the medical device may deliver ineffective or otherwise inappropriate therapy to the patient. In some cases, if a malfunctioning device is mistaken for a therapy that is truly ineffective for the particular patient, a therapy might be unnecessarily discontinued or have corrective action postponed. To help detect issues with a medical device or its components, integrity diagnostics may be performed.
• Medical devices that deliver electrical stimulation do so via electrodes located on, or implanted within the patient. The electrodes may be at a target location for receipt of the stimulation in order to provide the desired therapeutic effect. The medical device containing the stimulation generator may be at a different, more convenient location given its size or shape, e.g., outside of the patient, or implanted within the patient at a location capable of accommodating the medical device. The medical device may be coupled to the electrodes by one or more leads, each lead containing one or more conductors.
• Some medical devices perform integrity diagnostics to test the condition one or more of the electrodes, leads, or stimulation generator. One example of such an integrity test is to check the impedance between pairs of electrodes. This lead integrity test can be performed on leads and electrodes to verify that the leads and electrodes are functioning properly, and are positioned correctly. During testing, the medical device delivers a signal having a known electrical characteristic, e.g., current or amplitude, between two or more electrodes. Another electrical characteristic of the signal may be measured, and the impedance may be computed between electrodes using known fundamental relationships. The measured impedance value can give a medical professional or other user information relating to whether the electrodes involved in the test, as well as the conductors that coupled to those electrodes, are operating properly.
• Medical devices that deliver a drug or other therapeutic substance may do so via a catheter, or the like, that is at least partially implanted within the patient. The catheter conveys the therapeutic substance from a pump within the medical device to a target location within the patient. A partial or complete blockage of the catheter could prevent the therapeutic substance from reaching the delivery site in the patient or, in the case of a partial obstruction, could prevent an adequate supply of the therapeutic substance from reaching the delivery site in the patient. A leak (e.g., due to a tear or cut), small or large, can also prevent the therapeutic substance from reaching the delivery site in the patient. A leak can result in a double problem. In addition to the lack of therapeutic substance supplied to the delivery site of the patient, the therapeutic substance could be dispersed elsewhere in the body of the patient, which may create further issues.
• Some medical devices perform integrity diagnostics to test the condition one or more of the catheters or pumps. As an example, a catheter integrity test may measure the flow or pressure within the lumen of a catheter to detect tears or occlusions in the catheter. An abnormal increase in pressure within a lumen of a catheter may indicate an occlusion. Whereas, a decrease in pressure may indicate a tear. A decrease in flow may indicate either a tear or an occlusion. The measured flow and/or pressure values can give a medical professional or other user information relating to whether the catheter involved in the test is properly delivering a therapeutic substances to a target therapy delivery site.
SUMMARY
• In general, the invention is directed toward techniques for remotely monitoring the integrity of a medical device and its components. A remote networking device communicates with a medical device, e.g., an implantable medical device, via a network. The remote networking device sends a request for an integrity measurement to the medical device via the network. The request may be initiated by a user of the remote networking device, such as a clinician, or a technician for a manufacturer of the medical device. In response to the request, the medical device performs the requested integrity measurement. The medical device may transmit a result of the integrity measurement, e.g., a measured value, back to the remote networking device via the network.
• Any of a variety of integrity measurements may be requested at the remote networking device, and responsively performed by the medical device. For example, a lead impedance test, in which the medical device tests one or more lead-borne electrodes in the manner discussed above, may be requested at the remote networking device. As another example, catheter flow or pressure tests may be requested at the remote networking device. Additionally, the integrity of components of a stimulation generator, such as capacitors or voltage or current regulation circuitry, or of a pump mechanism, such as a stalled rotor or stuck piston, may be tested by the medical device as directed by a remote networking device. The integrity of any hardware or software component of an implantable or external medical device may be tested in response to a request from a remote networking device according to the invention.
• In one embodiment, the invention is directed to a method comprising receiving a request to perform an integrity measurement at a medical device from a remote networking device via a network, performing the integrity measurement at the medical device of at least one component within or coupled to the medical device in response to the request, and sending a result of the integrity measurement from the medical device to the remote networking device via the network.
• In another embodiment, the invention is directed to a medical device comprising a communication module, and a processor that receives a request from a remote networking device via a network and the communication module to perform an integrity measurement of at least one component within or coupled to the medical device, performs the integrity measurement in response to the request, and sends a result of the integrity measurement device to the remote networking device via the network and the communication module.
• In another embodiment, the invention is directed to a method comprising sending a request from a remote networking device via a network to a medical device to perform an integrity measurement, and receiving a result of the integrity measurement from the medical device via the network.
• In another embodiment, the invention is directed to a remote networking device comprising a communication module, and a processor to send a request to perform an integrity measurement to a medical device via the communication module and a network, and receive the result of the integrity measurement from the medical device via the network.
• In another embodiment, the invention is directed to a system comprising a medical device, and a remote networking device that sends a request to perform an integrity measurement to the medical device via a network, wherein the medical device performs the integrity measurement and sends a result of the integrity measurement to the remote networking device via the network.
• Embodiments of the invention may provide one or more advantages. For example, in some cases, a medical device does not perform integrity diagnostics unless requested by a clinician or other user using, for example, a medical device programmer. In such cases, the ability to remotely request integrity diagnostics may allow the condition of the medical device to be assessed without requiring a costly and time consuming clinic visit.
• Furthermore, in situations in which the medical device does automatically and periodically perform an integrity measurement, such measurements may not be occurring at a necessary time to detect an intermittent integrity issue with a particular component. For example, some lead fractures occur only intermittently, e.g., when a patient is within a particular posture or activity state. The causes of intermittent integrity problems may even be difficult to replicate during a clinic visit. In such cases, an integrity measurement may be remotely requested to occur at a time in which an intermittent integrity problem is likely to be detectable by an integrity measurement, e.g., when a patient is at home assuming the problematic postures or activities.
• The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.
BRIEF DESCRIPTION OF DRAWINGS
• FIG. 1 is a conceptual diagram illustrating an example system in which integrity diagnostics may be remotely requested.
• FIG. 2 is a conceptual diagram further illustrating some components of an example system in which integrity diagnostics may be remotely requested.
• FIG. 3 is a functional block diagram further illustrating the implantable medical device of the system ofFIG. 2.
• FIG. 4 is a functional block diagram illustrating another example implantable medical device which may receive requests to perform integrity diagnostics from a remote networking device.
• FIG. 5 is a functional block diagram illustrating components ofpatient programmer26 according to one embodiment of the invention.
• FIG. 6 is a flow diagram illustrating an example method of remotely requesting an integrity measurement.
DETAILED DESCRIPTION
• FIG. 1 is a conceptual diagram illustrating anexample system10 in which integrity diagnostics may be remotely requested.System10 includes an implantable medical device (IMD)14 implanted withinpatient12, aclinician programmer20, apatient programmer26, and aremote networking device4. As will be described in greater detail belowremote networking device4 sends integrity measurement requests toIMD14 vianetwork2, and receivesstatus data7 fromIMD14 via the network in response to the requests.IMD14 may communicate withnetwork2 directly or indirectly, e.g., viapatient programmer26. Although described herein with reference toIMDs14, the invention is not limited to embodiments in which the medical device that performs remotely requested integrity measurements is implanted.
• IMD14 may deliver electrical stimulation therapy, drug therapy, or both topatient12. Accordingly,IMD14 may be an implantable pulse generator that delivers electrical stimulation therapy topatient12 in the form of electrical pulses or substantially continuous time signals, a therapeutic agent delivery device that delivers a drug or other agent topatient12, or a device or devices that deliver both electrical stimulation therapy and a therapeutic agent topatient12. Although described herein with reference to medical devices that deliver a therapy to a patient, the invention is not so limited. For example, in some embodiments, a medical device may include sensors and act as a patient monitor without delivering therapy.
• IMD14 may deliver therapy according to one or more programs. Each program may include values for a number of therapy parameters, and the parameter values define the therapy delivered according to that program. In embodiments whereIMD14 delivers electrical stimulation therapy in the form of electrical pulses, the parameters may include voltage or current pulse amplitudes, pulse widths, as pulse rates, as well as combinations of electrodes selected for delivery of the stimulation and the polarities of the selected electrodes. In embodiments whereIMD14 includes a therapeutic agent delivery device instead of or in addition to an electrical stimulator, program parameters may define, as examples, flow rates, agent types or concentrations, and infusion types, e.g., continuous or bolus.
• A clinician (not shown) may useclinician programmer20 to specify one or more programs for the delivery of therapy byIMD14. For example, the clinician may interact with a user interface of the programmer to select values for various therapy parameters. A number of programs specified in this manner may be tested by controlling the IMD to delivery therapy according to the programs, and desirable programs may be selected. Selected programs may be transmitted fromclinician programmer20 to one or both ofIMD14 andpatient programmer26 for long term storage and use.
• Patient12 may usepatient programmer26 to control the delivery of therapy byIMD14. In particular,patient12 may usepatient programmer26 to activate or deactivate therapy and select which from among a plurality of available programs stored withinpatient programmer26 and/orIMD14 will be used byIMD14 to deliver therapy.Patient12 may also adjust the therapy by, for example, adjusting the values of the parameters of the therapy programs. Further, in some embodiments,patient programmer26 may sendstatus data8 fromIMD14 toremote networking device4 vianetwork2.
• IMD14,clinician programmer20, andpatient programmer26 may, as shown inFIG. 1, communicate with each other via local wireless communication.Clinician programmer20 andpatient programmer26 may, for example, communicate via wireless communication withIMD14 using RF telemetry techniques known in the art. For example,clinician programmer20 andpatient programmer26 may communicate with each other using any of a variety of local wireless communication techniques, such as RF communication according to the 802.11 or Bluetooth specification sets, infrared communication according to the IRDA specification set, or other standard or proprietary telemetry protocols.Clinician programmer20 andpatient programmer26 need not communicate wirelessly, however. For example,clinician programmer20 andpatient programmer26 may communicate via a wired connection, such as via a serial communication cable, or via exchange of removable media, such as magnetic or optical disks, or memory cards or sticks. Further,clinician programmer20 may communicate with one or both ofIMD14 andpatient programmer26 via remote telemetry techniques known in the art, e.g., utilizingnetwork2, which may comprise, for example, one or more of a local area network (LAN), wide area network (WAN), public switched telephone network (PSTN), or cellular telephone network.
• As will be described in further detail below,IMD14 may recordintegrity status data7 during normal operation, i.e., during operation outside of a clinical environment.Remote networking device4 may receivestatus data7 fromIMD14 vianetwork2 and may presentstatus data7 to a user.Remote networking device4 may also, in some example embodiments, analyzestatus data7, and take action or suggest action to the user based on the analysis. The term “status data” in this disclosure refers to the status ofsystem10. Status data may include data that relates to data from one or more sensors, alerts frompatient12 and/orIMD14, results of an integrity measurement, or any other data relevant to the status and operation ofsystem10.
• InFIG. 1,IMD14 communicates withremote networking device4 vianetwork2, which may include one or more of a local area network (LAN), a wide area network (WAN), a landline telephone network, a cellular phone network, the Internet, and a wireless network. In particular,remote networking device4 sends data to and receives data fromIMD14 overnetwork2.IMD14 may connect directly tonetwork2 or may connect tonetwork2 via a link device, such aspatient programmer26, a wireless modem, a base station that provides, for example, recharge features and other features forpatient programmer26, a laptop or desktop computer, or other computing device with a connection tonetwork2.
• IMD14 may send data, such asstatus data7, toremote networking device4 on demand, according to a schedule, or on an opportunistic basis.IMD14 may also transmit data toremote networking device4 when its memory is full. In embodiments, in whichIMD14 communicates withnetwork2 viapatient programmer26,patient programmer26 may temporary store and later transmit data toremote networking device4, e.g., when the patient programmer's memory is full. In embodiments in which data is transmitted toremote networking device4 on demand,patient12 or a clinician may initiate the transmission of data toremote networking device4. For example,patient12 may interact withpatient programmer26 by pressing one or more buttons on a keypad or selecting an item from a display of a graphical user interface, to initiate data transmission toremote networking device4. In another example, a clinician or other user atremote networking device4 may interact with a user interface (U/I)8 ofremote networking device4 to send a request toIMD14 to retrievestatus data7. In this example, the clinician may be located at a clinic or other remote location relative topatient12 and the request may be sent vianetwork2.
• In an example in which data is transmitted toremote network device4 according to a schedule,IMD14 orpatient programmer26 may store a schedule in local memory and send data toremote network device4 according to the schedule. Alternatively,remote networking device4 may store a schedule in amemory5, and aprocessor6 of the remote networking device may send a request to IMD14 (e.g., directly or indirectly via patient programmer26) to retrieve data according to the schedule. In either case, the schedule specifies when data is sent toremote networking device4. The schedule may specify that data is transmitted once per day, multiple times per day, once per week, multiple times per week, or at any other regular interval. The frequency at which data is transmitted may depend on the size of memory ofIMD14 and/orpatient programmer26 and the amount of data recorded byIMD14.
• In embodiments in which data is transmitted toremote networking device4 on an opportunistic basis,IMD14 and/orpatient programmer26 may transmit data overnetwork2 whenever they are within range of a link device that is connected tonetwork2. The link device may be a base station used for rechargingpatient programmer26 that includes a connection tonetwork2, or any of the other link devices previously described in this disclosure.
• It is also recognized thatIMD14 and/orpatient programmer26 may have substantially permanent connection tonetwork2, such as a wireless connection. In such cases,IMD14 and/orpatient programmer26 may transmit data toremote networking device4 in real-time. That is,IMD14 and/orpatient programmer26 may transmit data toremote networking device4 as data is generated.
• Retrieving data fromIMD14 may also be performed through real-time interaction betweenpatient12 and a clinician. In this case,patient12 and the clinician may communicate in real-time usingpatient programmer26 andremote networking device4, respectively. In this case, the clinician may send a request for data toIMD14. In some embodiments, the request travels toIMD14 viapatient programmer26.Patient programmer26 may promptpatient12 in response to receiving the request. For example,patient programmer26 may display a message that requires confirmation frompatient12 before sending data toremote networking device4.
• Aprocessor6 ofremote networking device4 may analyzestatus data7 relating to data from one or more sensors, alerts frompatient12 and/orIMD14, or results of an integrity measurement. For example,status data7 may include an alert frompatient12 thatpatient12 is not receiving adequate therapy. Based on the alert,processor6 may send a request toIMD14 vianetwork2 to perform an integrity measurement, such as a lead integrity test on all electrodes, a lead integrity test on the electrodes currently being used to deliver therapy, a catheter integrity test, and/or a pump motor stall test.
• As described previously, a lead integrity test may comprise measuring the impedance of an electrical path including an electrode, conductors that couple the electrode to an IMD, and tissue proximate to the electrode. Measuring the impedance of one or more electrical paths associated with one or more leads coupled to the IMD may aid in identifying dysfunctional electrical paths (e.g., paths that may be unable to provide adequate or reliable sensing or therapy due to, for example, degradation of the lead material, tissue growth proximate to an electrode, a short, or a fracture) among the paths provided by one or more leads coupled to the IMD. Copending U.S. Patent Publication No. 2006-0264777 by Touby A. Drew, entitled, “EVENT-BASED LEAD IMPEDANCE MONITORING” describes lead integrity tests in further detail.
• Another example of an integrity measurement is a catheter integrity test. A pressure differential measurement in one or more catheters may be performed as an integrity measurement. Such a measurement may aid to detecting flow issues within the catheter. If functioning properly, the pressure within a catheter may be substantially constant. Thus, for a given flow rate the pressure within a catheter may be approximately equal to a normal, expected level. Deviations from the normal pressure may indicate failure of the catheter. A pressure measurement below the normal level may indicate that the catheter is ripped or leaking. A pressure measurement above the normal level may indicate that the catheter is occluded or kinked. In other embodiments, the flow of a therapeutic substance within one or more catheters may be measured to identify issues (e.g., occlusions, kinks, tears, and leaks) with the catheters. U.S. Pat. No. 7,320,676 by Keith A. Miesel, entitled, “PRESSURE SENSING IN IMPLANTABLE MEDICAL DEVICES”, copending U.S. Patent Publication No. 2005-0245858 by Miesel et al., entitled, “BRANCHING CATHETER SYSTEMS WITH DIAGNOSTIC COMPONENTS”, and copending U.S. Patent Application Serial No. 2005-0241387 by Miesel et al., entitled, “DIAGNOSTIC METHODS FOR BRANCHING CATHETER SYSTEMS” describe catheter integrity tests in further detail.
• A pump motor stall test may be performed by driving a pump backwards (e.g., firing against the piston of the pump motor). A pump motor stall test may be used to determine if a problem with a therapeutic agent delivery system is due to a moving part within the pump or an issue with one or more of the catheters that deliver therapy from the pump to one or more target therapy delivery sites.
• Integrity measurements are not limited to the examples described above. Integrity measurements may generally comprise measurements that test the functionality of any component oftherapy system10. For example, performing an integrity measurement may comprise running software, hardware, and/or firmware diagnostics to test the integrity ofIMD14. Other examples testing an array of capacitors used to store energy for the delivery of stimulation pulses, or testing a power source of the IMD.
• After an integrity measurement is performed,remote networking device4 may receive a result of the integrity measurement. For example,remote networking device4 may receivestatus data7 including a result of the integrity measurement. In some embodiments,IMD14 orpatient programmer26 may perform a preliminary analysis based on the result of the integrity measurement. Based on the preliminary analysis,IMD14 orpatient programmer26 may change a mode of operation ofIMD14 to address any issue identified.IMD14 and/orpatient programmer26 may transmit status data indicating any change in the mode of operation ofIMD14 toremote networking device4 along with the result of the integrity measurement.
• In some embodiments,processor6 ofremote networking device4 may analyze the result of the integrity measurement to identify problems withtherapy system10 and, upon identifying a problem, suggest a correction for the identified problem, e.g., to a user via U/I8. In embodiments in whichIMD14 orpatient programmer26 performed a preliminary analysis, the analysis performed byprocessor6 may be more extensive. Ifprocessor6 identifies an issue withIMD14,processor6 may sent a command toIMD14 vianetwork2 to change a mode of operation ofIMD14. For example,processor6 may identify a dysfunctional electrical path and send a command topatient programmer28 and/orIMD14 to lock out the electrode(s) of the dysfunctional path to prevent the electrode(s) from being selected to deliver therapy.Processor6 may analyze the result of the integrity measurement as the result is received. In other embodiments, the result may be stored asstatus data7 withinmemory5 ofremote networking device4 for analysis at a later time.
• In other embodiments,remote networking device4 may send a request toIMD14 vianetwork2 to perform a more sophisticated integrity measurement based on the result of an initial integrity measurement. For example,remote networking device4 may request an additional lead integrity test at a more accurate setting (e.g., a higher amplitude) or request that the integrity measurement be repeated to allow statistical analysis over time.
• The analysis ofstatus data7 and the generation of requests and/or commands atremote networking device4 may be performed byprocessor6 ofremote networking device4, an authorized user ofremote networking device4, or any combination thereof. For example,memory5 ofremote networking device4 may store instructions thatprocessor6 may execute based onstatus data7.Remote networking device4 may generate requests for integrity measurements, analyzestatus data7, and generate commands to address issues withIMD14 in a responsive and automatic manner.
• In other embodiments,processor6 may present data received fromIMD14 to an authorized user, such as a clinician, a technician, a manufacturer, or another trained practitioner, via U/I8.Status data8 may be reviewed by one or more authorized users and requests for integrity measurements and commands changing the mode of operation ofIMD14 may be sent toIMD14 vianetwork2 based on input from one or more of these users. Also, in some embodiments, requests to perform integrity measurements may be sent toIMD14 based on a schedule or as requested by an authorized user. Such requests need not be based onstatus data8 received fromIMD14.
• Remote networking device4 comprises a computing device, such asclinician programmer20, a desktop or laptop computer, workstation, PDA, or the like. In some embodiments,remote networking device4 may comprise a plurality of networked devices, such as a server and a workstation. U/I may comprise a display and input media, such as a keyboard, keypad, or pointing device. As illustrated inFIG. 1,remote networking device4 comprises acommunication module9 for communicating withnetwork2.Communication module9 may comprise any known network interface, such as an Ethernet interface.
• Processor6 may comprise any one or more of a microprocessor, application specific integrated circuit (ASIC), digital signal processor (DSP), discrete logic circuitry, or the like.Memory5 may comprise any fixed or removable, volatile or non-volatile medium, such as one or more of a random access memory (RAM), read-only memory (ROM), CD-ROM, hard disk, flash memory, or the like.Memory5 may comprise program instructions that, when executed byprocessor6,cause processor6 andremote networking device4 to provide the functionality described herein.
• Remotely requesting an integrity measurement and receiving results of the measurement remotely may provide a patient and IMD access to a remotely-located clinician, manufacturer, and/or other authorized user without requiring a clinic visit. Additionally, a remotely located computing device may contain more processing power and memory and be more easily updated with new data processing algorithms thanIMD14 orpatient programmer26. Also, determining which integrity measurements to perform and analyzing data remotely may help prolong the battery life ofIMD14 and/orpatient programmer26.
• FIG. 2 is a conceptual diagram illustrating components of asystem10 in greater detail. In particular,FIG. 2 illustratesIMD14,patient programmer26, andclinician programmer20 in greater detail. In the illustrated example,IMD14 is coupled totherapy delivery elements34A and34B (collectively “therapy delivery elements34”). In the example ofFIG. 2,IMD14 is implanted in the abdomen ofpatient12. However, in other embodiments,IMD14 may be external or subcutaneously implanted at another location in the body of a patient12 (e.g., in a chest cavity, lower back, or buttocks of patient12). In the illustrated embodiment,IMD14 is coupled to twotherapy delivery elements28 to deliver therapy to two target therapy delivery sites. In other embodiments,IMD14 may be coupled to a single therapy delivery element or more than two therapy delivery elements, e.g., to deliver therapy to more or fewer target therapy delivery sites.
• In the embodiment oftherapy system10 shown inFIG. 2, the target therapy delivery sites are proximate to thespinal column32. Accordingly,therapy delivery elements28 may deliver therapy to, for example,spinal column32 or surrounding tissue. Therapy delivery to the spinal column or surrounding tissue may help treat, for example, chronic pain or spinal cord injury.IMDs14 according to the invention, however, may deliver a variety of therapies formulated for different disorders or symptoms, such as tremor, Parkinson's disease, multiple sclerosis, cerebral palsy, amyotrophic lateral sclerosis, dystonia, torticollis, epilepsy, pelvic floor disorders, gastroparesis, paralysis (e.g., functional electrical stimulation (FES) of muscles) obesity, pelvic floor disorders, urinary control disorders, fecal control disorders, interstitial cystitis, sexual dysfunction, and pelvic pain. Thus, in alternate embodiments, the target therapy delivery sites to whichtherapy delivery elements28 extend may include or be proximate to any other nerve or tissue site in the body ofpatient12. For example, target therapy delivery sites may include a pelvic nerve, pudendal nerve, stomach, bladder, or within a brain or other organ ofpatient12, or within a muscle or muscle group ofpatient12.System10 may include any type of IMD for delivering therapy topatient12, such as an electrical stimulator or a therapeutic agent delivery device.
• Clinician programmer20 may, as shown inFIG. 2, be a handheld computing device.Clinician programmer20 comprises a user interface that may include adisplay22, such as a LCD or LED display, to display information to a user. The user interface forclinician programmer20 may also include akeypad24, which may be used by a user to interact withclinician programmer20. In some embodiments,display22 may be a touch screen display, and a user may interact withclinician programmer20 viadisplay22. A user may also interact withclinician programmer20 using a peripheral pointing device, such as a stylus or mouse.Keypad24 may take the form of an alphanumeric keypad or a reduced set of keys associated with particular functions.Display22 may also present so-called soft keys for selection by the user.
• Patient programmer26, as shown inFIG. 2, may also be a handheld computing device.Patient programmer26 includes a user interface which may comprise adisplay28 and akeypad30, to allowpatient12 to interact withpatient programmer26. In some embodiments,display28 may be a touch screen display, andpatient12 may interact withpatient programmer26 viadisplay28.Patient12 may also interact withpatient programmer26 using a peripheral pointing device, such as a stylus or mouse. As previously described, patient12 may usepatient programmer26 to control the delivery of therapy byIMD14, andpatient programmer26 may act as an intermediary for communication betweenIMD14 andnetwork2.
• FIG. 3 is a functional block diagram illustrating anexample IMD14A that takes the electrical stimulator. In the illustrated embodiment,IMD14A includes a sensor42, aprocessor46, acommunication module48,memory50,power supply52, andtherapy module54A.Therapy module54A is coupled totherapy delivery elements40A and40B (collectively “therapy delivery elements40”).
• In the illustrated embodiment, therapy delivery elements40 are leads including electrodes configured to deliver electrical stimulation topatient12.Leads40A and40B respectively includeelectrodes44A-44D andelectrodes44E-44H (collectively, “electrodes44”). The configuration, type, and number of leads and electrodes illustrated inFIG. 3 are merely exemplary, and, in other embodiments, any other configuration, type, and/or number of electrodes may be used. Electrodes44 may be ring electrodes or other types of electrodes such as cuff electrodes, paddle electrode leads, and electrodes formed on a housing ofIMD14A. In embodiments in which electrodes44 are ring electrodes, electrodes44 may be positioned at various positions along the length of leads40, e.g., at a distal end, a proximal end, or medially located between the distal and proximal ends of leads40.
• Each of leads40 may have multiple conductors, each corresponding to one or more of electrodes44, to electrically connect electrodes44 toIMD14A. Leads40 may be directly connected toIMD14A, or may be connected toIMD14A via one or more lead extensions. Conductors within a lead extension couple the conductors within a lead toIMD14A. An electrode, the conductors that couple the electrode toIMD14A, and tissue proximate to the electrode may be referred to as an electrical “path,” through whichIMD14A may sense electrical activity withinpatient12 and/or deliver stimulation topatient12.
• Therapy module54A may include an implantable stimulation generator or other stimulation circuitry, e.g., capacitive elements and switches that delivers electrical signals topatient12 via at least some of electrodes44 under the control ofprocessor46.Processor46 may controltherapy module54A to deliver stimulation therapy according to one or more selected programs. For example,processor46 may controltherapy module54A to deliver electrical pulses with the amplitudes and widths, and at the rates specified by the one or more selected programs.Processor46 may also controltherapy module54A to deliver the pulses via a selected subset of electrodes44 with selected polarities, as specified by the selected programs.Processor46 may include any one or more of a microprocessor, a controller, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA), discrete logic circuitry, or the like.
• Memory50 may store program instructions defining therapy programs that are available for therapy delivery viatherapy module54A.Memory50 may also storestatus data7 recorded byprocessor46. As previously described in this disclosure,status data7 may include data from one or more sensors, alerts frompatient12 and/orIMD14A, results of an integrity measurement, or any other data relevant to the status and operation of the therapy delivery system.Memory50 may also store program instructions that, when executed byprocessor46,cause processor46 andIMD14A to provide the functionality ascribed to them herein.Memory50 may include for example any volatile, non-volatile, magnetic, optical, or electrical media. For example,memory50 may include any one or more of a random access memory (RAM), read-only memory (ROM), non-volatile RAM (NVRAM), electronically erasable programmable ROM (EEPROM), flash memory, or the like.
• Communications module48 includes circuitry for communication withclinician programmer20,patient programmer26, and/orremote networking device4.Communications module48 may include circuitry for wireless, RF communication according to any of a variety of local wireless communication standards, such as the Bluetooth standard, any of the IEEE 802.11 standards, or a proprietary medical device telemetry protocol.Communications module48 may allowprocessor46 to connect tonetwork2 to receive requests fromremote networking device4 and/or transmitstatus data7 toremote networking device4.Processor46 may transmitstatus data7 toremote networking device4 viacommunications module48 in response to receiving a request fromremote networking device4. Alternatively,processor46 may automatically transmitstatus data7 toremote networking device4 viatelemetry interface48 in accordance with a schedule, on an opportunistic basis, or based on memory capacity.
• As further shown inFIG. 3,system10 may include one or more sensors that sense activity or physiological conditions withinpatient12. Sensors may be, for example, activity, chemical, optical, temperature, pressure, and/or electrical sensors. Although the example ofFIG. 3 includessensor42A withinIMD14A, sensors may in some embodiments be located outside of anIMD14, and communicate data representing activity or a physiological condition to theIMD14 by a wired connection, e.g., lead, or wireless telemetry, e.g., viacommunication module48. Data fromsensor42A may be received byprocessor46, and stored inmemory52.Sensor42A may sense activity or physiological conditions pertinent to the control of therapy delivered byIMD14A.
• The activity and/or physiological conditions sensed bysensor42A may be useful in identifying a state or phase of physiological activity, or a transition between different phases of activity.Processor46 may use data received fromsensor42A to adjust therapy delivery. For example,processor46 may use data received fromsensor42A to adjust therapy parameters such as voltage or current pulse amplitudes, pulse widths, pulse rates, electrode combinations, or polarities of selected electrodes.Processor46 may adjust therapy delivery based on other data, such as user input or timing data, either individually or in combination with data received fromsensor42A.
• The physiological parameter detected bysensor42A may reflect the severity or prevalence of pain, movement disorders, epilepsy, mood disorders, cardiac disorders, gastrointestinal or urinary disorders, or side-effects associated with the treatment of such symptoms or disorders. Data fromsensor42A stored withinmemory50 may include raw data derived from the signals output by the sensor, averages or other statistical representations of such data, or any other metric derived from such data.
• The illustrated components ofIMD14A receive energy from apower source52, which may be a battery or other suitable power source.Power source52 may take the form of a small, rechargeable or non-rechargeable battery, or an inductive power interface that transcutaneously receives inductively coupled energy. In the case of a rechargeable battery,power source52 similarly may include an inductive power interface for transcutaneous transfer of recharge power.
• Memory50 may store instructions that may be executed byprocessor46 to perform integrity measurements. For example,remote networking device4 may send a request toIMD14A vianetwork2 which causesprocessor46 to perform an integrity measurement according to instructions stored inmemory50. In other embodiments, instructions for performing the integrity measurement may be sent toIMD14A vianetwork2. In some embodiments,memory50 may store results of integrity measurements.
• One example of a diagnostic integrity measurement that may be performed byprocessor46 is a lead integrity test. A lead integrity test may comprise measuring the impedance of an electrical path including an electrode (e.g., one of electrodes44), conductors that couple the electrode toIMD14A, and tissue proximate to the electrode. Measuring the impedance of one or more electrical paths associated with leads40 coupled toIMD14A may aid in identifying dysfunctional electrical paths (e.g., paths that may be unable to provide adequate or reliable sensing or therapy due to, for example, degradation of the lead material, tissue growth proximate to an electrode, a short, or a fracture) among the paths provided by leads40 coupled toIMD14A. In general, integrity measurements performed byprocessor46 may comprise measurements that test the functionality, accuracy, operating condition, or performance of any component oftherapy system10A. For example, performing an integrity measurement may comprise running software, hardware, and/or firmware diagnostics to test the integrity ofIMD14A.
• FIG. 4 is a functional block diagram illustrating another IMD embodiment. In particular,FIG. 4 illustrates anIMD14B that delivers a therapeutic agent to patient12 viatherapy delivery elements56A and56B (collectively “therapy delivery elements56”). Therapy delivery elements56 may also be referred to as therapeutic agent delivery elements or catheters. Similar toIMD14A,IMD14B includes sensor42,processor46,communications module48,memory50,power supply52, and atherapy module54B.
• Each of catheters56 may have an elongated tubular body with an inner lumen. With reference toFIG. 4, each elongated body may include a proximal opening to receive the therapeutic agent fromIMD14B and adistal outlet60A,60B (collectively, “outlets60”) for delivery of the therapeutic agent to one or more target therapy delivery sites. Additionally or alternatively, the elongated body may include one or morelateral outlets58 formed in a lateral wall of the elongated body that provide fluid communication between the inner lumen and the outside of the elongated body.Outlets58 may be positioned at various axial positions along the length of the elongated body, as well as various circumferential positions.Lateral outlets58 may be concentrated towards a distal end of the catheter. The configuration, type, and number of outlets illustrated inFIG. 4 are merely exemplary, and, in other embodiments, any other configuration, type, and/or number of outlets may be used.
• Therapy module54B may include one or more therapeutic agent reservoirs and one or more pump units that pump the therapeutic agent from the fluid reservoirs through catheters56 to the one or more target therapy delivery sites under the control of processor46B. The fluid reservoirs may provide access for filling, e.g., by percutaneous injection of a therapeutic agent via a self-sealing injection port. Catheters56 may, for example, deliver, i.e., infuse or disperse, a therapeutic agent from the fluid reservoirs to the same or different target therapy delivery sites withinpatient12 under the control ofprocessor46.Processor46 may control which therapeutic agents are delivered and the dosage of the therapeutic agents delivered topatient12. For example,processor46 may controltherapy module56B to delivery a therapy according to flow rates, agent types or concentrations, and infusion types, e.g., continuous or bolus, specified by the one or more selected programs. As described with respect toFIG. 3,processor46 may include any one or more of a microprocessor, a controller, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA), discrete logic circuitry, or the like.
• Although “therapeutic agent delivery device” and “therapeutic agent” is used for purposes of explanation, other substances may be delivered topatient12. For example,IMD14B may deliver saline solution, fluoroscopy agents, or disease diagnostic agents, which may or may not be intended to have a therapeutic effect, topatient12. Any therapeutic, diagnostic, or other substance may be delivered usingIMD14B. In some embodiments, the substance delivered usingIMD14B may contain one or more drugs. The drugs will typically be fluids (e.g., liquids) or contained in fluid carriers (e.g., liquid carriers) as either solutions or mixtures.
• Substances delivered usingIMD14B may be intended to have a therapeutic effect such as pharmaceutical compositions, genetic materials, biologics, and other substances. Pharmaceutical compositions are typically chemical formulations intended to have a therapeutic effect such as intrathecal antispasmodics, pain medications, chemotherapeutic agents, and the like. Pharmaceutical compositions may be configured to function in an implanted environment with characteristics such as stability at body temperature to retain therapeutic qualities, concentration to reduce the frequency of replenishment, and the like. Genetic materials include substances intended to have a direct or indirect genetic therapeutic effect such as genetic vectors, genetic regulator elements, genetic structural elements, DNA, and the like. Biologics include substances that are living matter or derived from living matter intended to have a therapeutic effect such as stem cells, platelets, hormones, biologically produced chemicals, and the like.
• Memory50 may store program instructions defining therapy programs that are available for therapy delivery viatherapy module54B.Memory50 may also storestatus data7 recorded byprocessor46. As previously described in this disclosure,status data7 may include data from one or more sensors, alerts frompatient12 and/orIMD14, results of an integrity measurement, or any other information relevant to the status and operation of the therapy delivery system. As indicated above,memory50 may include instructions that, when executed byprocessor46,cause processor46 andIMD14B to provide the functionality described herein.
• LikeIMD14A,IMD14B includes asensor42A that senses activity or physiological conditions withinpatient12. Additionally, asensor42B is coupled toIMD14B viacatheter56A.Sensor42B may sense, for example, flow or pressure withincatheter56A, and communicate sensed data toIMD14B via a wired connection of wireless telemetry.
• One example of an integrity measurement that may be performed byprocessor46 inIMD14B is a catheter integrity test. A catheter integrity test may comprise measuring a pressure differential in one of catheters56, e.g.,catheter56A via sensor42C. Such a measurement may aid to detecting flow issues within catheters56. If functioning properly, for a given flow rate, the pressure within catheter56 may be approximately equal to a normal, expected level. Deviations from the normal pressure may indicate failure of a catheter56. In other embodiments, the flow of a therapeutic substance within a catheter56 may be measured (e.g., via sensor42C) to identify issues (e.g., occlusions, kinks, tears, and leaks) with the catheter.
• Additionally or alternatively, a pump motor stall test may be performed onIMD14B by driving a pump oftherapy module54B backwards (e.g., firing against the piston of the pump motor). A pump motor stall test may be used to determine if a problem with a therapeutic agent delivery byIMD14B is due to a moving part within the pump or an issue with one or more of catheters56 that deliver therapy from the pump to one or more target therapy delivery sites.
• As another example,processor46 may perform an integrity measurement by changing an operating parameter of the pump oftherapy module54B and monitoring howtherapy system10B is affected. For example, a pump stroke that differs substantially from the pump stroke used to deliver therapy may be used to aid in determining iftherapy system10B is functioning properly and, if applicable, what is causingtherapy system10B to function improperly. The pump stroke may be increased and the pulses may be distributed to maintain a similar average flow rate of therapeutic agent topatient12. The manner in which pulses are delivered topatient12 can be used to identify issues withtherapy delivery system10B and may potentially help address the issues identified. For example, ifcatheter56B is partially occluded, a higher pulse stroke may aid in clearing the occlusion fromcatheter56B.
• Integrity measurements are not limited to the examples described above. In general, integrity measurements may comprise measurements that test the functionality of any component oftherapy system10B. For example, performing an integrity measurement may comprise running software, hardware, and/or firmware diagnostics to test the integrity ofIMD14.
• FIG. 5 is a functional block diagram illustrating components ofpatient programmer26 according to one embodiment of the invention. As illustrated byFIG. 5,programmer26 may include aprocessor70, user interface (U/I)72,communication module74, andmemory76. A user, such aspatient12, may interact withprocessor70 via U/I52, which may include, for example,display28 and keypad30 (FIG. 2).Processor70 may communicate withIMD14,clinician programmer20, andnetwork2 viacommunication module74, which may include any RF or wired interface.Memory76 may storestatus data7 received fromIMD14.Memory76 program instructions that, when executed byprocessor70cause processor70 andprogrammer26 to provide any of the functionality ascribed to them herein, such as acting as an intermediary betweenIMD14 andremote networking device4, providing an interface for communication bypatient12 with the remote networking device, collectingstatus data7, analyzingstatus data7, and the like.
• FIG. 6 is a flow chart illustrating an example method of remotely requesting an integrity measurement.Remote networking device4 may send a request toIMD14 vianetwork2 to perform an integrity measurement, such as a lead integrity test on all electrodes, a lead integrity test on the electrodes currently being used to deliver therapy, a catheter integrity test, and/or a pump motor stall test (80). The request sent fromremote networking device4 toIMD14 may be based onstatus data7, a request from a clinician or other trained practitioner, or a schedule.IMD14 performs the integrity measurement according to the request received via network2 (82). In some embodiments, the request comprises instructions describing how to perform the integrity measurement. In other embodiments, the instruction may be stored withinIMD14, and the request sent fromremote networking device4 may promptIMD14 to access the instructions.
• A result of the integrity measurement is sent fromIMD14 toremote networking device4 via network2 (84).Remote networking device4, a clinician, or another trained practitioner may analyze the result of the integrity measurement to identify problems withtherapy system10. If a problem is identified, a correction may be sent toIMD14 vianetwork2. For example,remote networking device4 may identify a dysfunctional electrical path and send a request topatient programmer26 and/orIMD14 to lock out the electrode(s) of the dysfunctional path to prevent the electrode(s) from being selected to deliver therapy.Remote networking device4 may also act to cause a follow-up visit, by notifying the patient or clinician, that would address the issue by surgical intervention or other means.
• In other embodiments,remote networking device4, the clinician, or the trained practitioner may require additional information fromIMD14 in order to identify potential issues. For example, based on the results of the initial integrity measurement,remote networking device4 may send a request toIMD14 vianetwork2 to perform a more sophisticated integrity measurement.Remote networking device4 may, for example, request an additional lead integrity test at a more accurate setting (e.g., a higher amplitude) or request that the integrity measurement be repeated to allow statistical analysis over time.
• Various embodiments of the invention have been described. These and other embodiments are within the scope of the following claims.

Claims (29)

1. A method comprising:

receiving a request to perform an integrity measurement at an implantable medical device from a remote networking device via a network;

performing the integrity measurement at the implantable medical device of at least one component within or coupled to the implantable medical device in response to the request; and

sending a result of the integrity measurement from the implantable medical device to the remote networking device via the network.

2. The method ofclaim 1, further comprising changing a mode of operation of the implantable medical device based on the result of the integrity measurement.

3. The method ofclaim 2, wherein changing a mode of operation comprises receiving a command from the remote networking device via the network at the implantable medical device to change the mode of operation.

4. (canceled)

5. The method ofclaim 1, wherein the implantable medical device comprises at least one of a pump or a stimulator.

6. The method ofclaim 1, wherein the implantable medical device comprises a stimulator coupled to a lead including one or more electrodes, and performing the integrity measurement comprises testing an electrical path from the medical device to at least one of the electrodes.

7. The method ofclaim 1, wherein the implantable medical device comprises a pump coupled to one or more catheters, and performing the integrity measurement comprises measuring at least one of pressure or flow within a lumen of at least one of the catheters.

8. The method ofclaim 1, wherein performing the integrity measurement comprises performing at least one of software, hardware, or firmware diagnostics.

9. An implantable medical device comprising:

a communication module; and

a processor that receives a request from a remote networking device via a network and the communication module to perform an integrity measurement of at least one component within or coupled to the implantable medical device, performs the integrity measurement in response to the request, and sends a result of the integrity measurement device to the remote networking device via the network and the communication module.

10. The implantable medical device ofclaim 9, wherein the processor changes a mode of operation of the implantable medical device based on the result of the integrity measurement.

11. The implantable medical device ofclaim 10, wherein the processor receives a command from the remote networking device via the network and the communication module to change the mode of operation.

12. (canceled)

13. The implantable medical device ofclaim 9, wherein the implantable medical device comprises at least one of a pump or a stimulator.

14. The implantable medical device ofclaim 9, wherein the implantable medical device comprises a stimulator coupled to a lead including one or more electrodes, and the processor performs the integrity measurement by testing an electrical path from the medical device to at least one of the electrodes.

15. The implantable medical device ofclaim 9, wherein the implantable medical device comprises a pump coupled to one or more catheters, and the processor performs the integrity measurement by measuring at least one of pressure or flow within a lumen of at least one of the catheters.

16. The implantable medical device ofclaim 9, wherein the processor performs the integrity measurement by performing at least one of software, hardware, or firmware diagnostics.

17. A method comprising:

sending a request from a remote networking device via a network to an implantable medical device to perform an integrity measurement; and

receiving a result of the integrity measurement from the implantable medical device via the network.

18. The method ofclaim 17, further sending a command to the implantable medical device via the network to change a mode of operation of the medical device based on the result of the integrity measurement.

19. The method ofclaim 17, wherein the implantable medical device comprises a stimulator coupled to a lead including one or more electrodes, and sending a request to perform an integrity measurement comprises sending a request to test an electrical path from the implantable medical device to at least one of the electrodes.

20. The method ofclaim 17, wherein the implantable medical device comprises a pump coupled to one or more catheters, and sending a request to perform an integrity measurement comprises sending a request to measure at least one of pressure or flow within a lumen of at least one of the catheters.

21. A remote networking device comprising:

a communication module; and

a processor to send a request to perform an integrity measurement to an implantable medical device via the communication module and a network, and receive the result of the integrity measurement from the implantable medical device via the network.

22. The remote networking device ofclaim 21, wherein the processor sends a command to the implantable medical device via the communication module and the network to change a mode of operation of the medical device based on the result of the integrity measurement.

23. The remote networking device ofclaim 22, further comprising a user interface, wherein the processor presents the result of the integrity measurement to a user via the user interface, and sends the command to the implantable medical device in response to a user request received via the user interface.

24. The remote networking device ofclaim 22, wherein the processor analyzes the result of the integrity measurement, and automatically sends the command to the implantable medical device.

25. A system comprising:

an implantable medical device; and

a remote networking device that sends a request to perform an integrity measurement to the implantable medical device via a network, wherein the implantable medical device performs the integrity measurement and sends a result of the integrity measurement to the remote networking device via the network.

26. The method ofclaim 5, further comprising receiving a command from the remote networking device in response to the result of the integrity measurement, the command locking out at least one of the electrodes from being selected for delivery of therapy.

27. The implantable medical device ofclaim 13, wherein the processor receives a command from the remote networking device in response to the result of the integrity measurement via the network and the communication module locking out at least one electrode from being selected for delivery of therapy.

28. The method ofclaim 19, further comprising sending a command from the remote networking device in response to and based on the result of the integrity measurement, the command locking out at least one of the electrodes from being selected for delivery of therapy.

29. The remote networking device ofclaim 22, wherein the implantable medical device comprises a stimulator coupled to a lead including one or more electrodes, the integrity measurement comprises testing an electrical path from the medical device to at least one of the electrodes, and the processor sends a command in response to and based on the result of the integrity measurement, the command locking out at least one of the electrodes from being selected for delivery of therapy.

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